Yet again, something dreadful and new which he doesn't understand is going viral. Today's fad is, you paint a black vertical rectangle on the wall, or on a mirror, or over the top of a picture. used to describe a piece of information, a video, an image, etc.

Understanding the Context

that is sent rapidly over the internet and seen by large numbers of people within a short time. Within 24 hours, the video went viral on YouTube and Facebook. Definition of viral adjective in Oxford Advanced Learner's Dictionary.